1. Field of the Invention
The present invention relates to a light-emitting device or a lighting device including an EL element in which a light-emitting layer containing an organic compound is interposed between a pair of electrodes.
2. Description of the Related Art
In recent years, a light-emitting element (also referred to as an electroluminescent (EL) element) in which a light-emitting layer (hereinafter also referred to as an EL layer) containing an organic compound is interposed between a pair of electrodes has been actively developed. Lighting has attracted attention as one of application fields of the light-emitting element. This is because a lighting device including the EL element has features different from those of other lighting devices; for example, the lighting device including the EL element can be thin and light, and perform surface emission.
In addition, an EL element has attracted attention also in terms of its high efficiency of conversion from power into light and its high potential for saving energy. It is also a unique feature of an EL element that, depending on a substrate selected, it is possible to provide a lighting device having flexibility, a lighting device having high resistance against an impact such as physical destruction, or a very lightweight lighting device.
A lighting device including an organic EL element is disclosed in Patent Document 1.